Online Activities: Fossils

Preparing Fossils

In order to study a fossil, we must be able to see it. But sometimes the fossil is hidden in the matrix - the rock that surrounds it.

The impression of the fossil may be very faint, or the fossil may be the same colour as the matrix. Sometimes the fossil is very fragile and must be repaired and strengthened before it can be studied. Some fossils are so tiny that they can only be studied using a microscope.

Paleontologists have to use a variety of preparation techniques to make the fossils easier to see.One technique is to make a mould of the fossil out of latex (liquid rubber). Sometimes the fossil's impression is easier to study than the fossil itself.

Some fossils can be scrubbed with soap and water. Unwanted rock and dirt may be removed carefully from around the fossil using small brushes, dental tools, or an electric or air powered engraving tool. If the rock around the fossil is very crumbly, it may be coated with a consolidant, a type of light glue that holds the rock together.

 

 

A technician prepares a fossil using an engraving tool to carve away the unwanted rock.
photo: D. Rudkin

This specimen has not been prepared. Parts of a few trilobite fossils are visible on the surface. There are probably more fossils hidden in the rock.

This specimen has been prepared using an air abrasive tool that acts like a miniature sand blaster to carve away the unwanted rock.